That wattmeter seems to be reading something odd. 32 volts and over 8 amps does not add up to 80 watts.
I have a PowerStar W7 inverter, I added a choke in series with the transformer on it and it did drop the idle current by about half.
My 12 volt 3000 watt powerstar was drawing around 100 watts idle current when I bought it, I managed to get that down to just under 40 watts by adding the choke. As it was my primary inverter it was worth doing.
Pete